1. Field of the Invention
This invention relates to a high precision ECR plasma process for etching and coating.
2. Description of the Prior Art
The conventional ECR plasma process employs electron cyclotron resonance due to a constant magnetic field of 0.0875 T in the plasma state that can be used for etching and coating.
In the conventional ECR plasma process which uses a constant magnetic field, a rapid ion rotation current is set up so that the ions scatter. The .theta. offset angle of an ion beam in a substrate therefore increases as shown in FIG. 3 so that anisotropic patterning becomes difficult. Further, as a result of continuous irradiation, hollow cavities are formed by vapor and the substrate is heated over a large part of its area so that it is difficult to achieve high patterning precision.